Logging into one host and then making a connection to another host (also known as host hopping) is a feature that is commonly used in today's networks. Products such as Linux™, allow a user to host hop using commands, such as ssh (Secure SHell), telnet, File Transfer Protocol (FTP), and secure copy. The use of host hopping allows an administrator the ability to manage hosts on the network.
However, host hopping may open up a network to security breaches. If a user who has rights on a first host uses host hopping to gain access to a second host that the user does not have rights to access, a security breach can occur. These types of breaches can cause the loss of secure information.
In an attempt to protect against host hopping, current systems have the ability to monitor a communication session at a firewall. An administrator or software can monitor commands that are sent by a remote user accessing a host through the firewall. This solution does provide some additional protection. However, a malicious user can still breach the security of a second host by using macros or other scripts that are not detected by the administrator or software.